With the aid of computation including the use of a small on-line laboratory computer, methods for decomposing the pneumotachograph and synthesis of the chemosensitive mechanism of respiration are studied. In the first the flow record is regarded as a hybrid modulated wave and the frequency and amplitude envelopes are extracted by means of digital filters. These envelopes show that the respiratory transient to CO2 inhalation or to hypoxia are rather precisely measurable and that the central CO2 response has an unexplained time delay. Other studies have shown a dissociable coupling between the pulmonary reflex mechanism and CO2 sensitivity. Based upon these observations and the literature, a computer model of chemosensitivity is being studied to endeavor to explain some of the dynamics of the CO2 control of ventilation.